What is Network Service Assurance?
Network service assurance is the institution of policies and processes by network providers and telecommunication providers to guarantee an optimal customer experience. It measures the impact changes to the network have on security, network availability, and compliance. A pursuit that has become more challenging in recent years since virtualization and software-defined network (SDN) trends have changed the dynamics of networks making them less manageable using traditional techniques.
Network service assurance attempts to quantify risk by analyzing network data (config files, network state, network traffic, error logs and performance data) and identifying errors within this data, such as incorrect configurations in network equipment, that may result in connectivity issues, traffic degradation or network outages.
Ultimately, customer experience is the primary measurement of a network’s performance, however, providers also must meet objective Service Level Agreements (SLA) that specify the performance parameters within which a service is provided. They are an integral part of IT vendor contracts, including protecting both parties in legal matters, SLAs provide the technical understanding between provider and customer, therefore it is vital that the SLA be aligned with business objectives. The collection of policies and processes by network providers, called network assurance, attempt to support, and meet or exceed these agreements between network suppliers and their end customers.
A Unified Approach to End-to-End Service Assurance
Network providers face an inundation of new technologies that create complex integration challenges when securing end-to-end network service assurance. Many have deployed the Unified Approach, a popular method for ensuring end-to-end service assurance, that shifts focus from a technology and product centric view to a business perspective instead encompassing customer and service concerns. The traditional belief that if technology silos are operating well then the business functions must be too and subsequently the user experience, but that is outdated and counterproductive. Data from each silo must work together to create a rich customer experience.
The Unified Approach overcomes the siloing effect disparate technologies have that make up large networks by gathering data from all sources and then normalizing it. By normalizing all network data across any format, any protocol, or data feed, it can be monitored and analyzed together providing end-to-end visibility and insight of the network. Further, automation can be applied to root cause analysis and incident scope detection enabling teams to respond in real-time to service performance issues.
Because this “data normalization” approach creates a resilient, adaptive service-oriented platform across all domains, network infrastructure silos can be easily changed, swapped out, and even new integrations developed underneath the service operations layer without disturbing customer experience operations.
In a unified platform approach, data is collected from every source (fault/event, metrics, and topology data) and then normalized to be stored in a unified data warehouse, or assurance warehouse. From this data source a single truth can be analyzed, filtered, monitored, and tracked using sophisticated alerting engines. Then a single view can be presented to network and service managers for immediate use and stored for historical reports.
Cisco Software Driven Network Service Assurance
On a practical level, large data centers today are growing at exponential rates, and so is their complexity. These enterprises cannot possibly maintain their networks without the help of automation. What happens if a top-level policy is changed? Or a configuration file changed? How can network integrity be assured and stay operational? Or stay compliant with regulations?
Cisco has labeled these uncertainties in complex networks “network assurance gaps” and the traditional way of solving them was to exhaustively and manually test the network for every possible scenario. This is clearly not feasible in most situations. By borrowing from the field of formal verification, Cisco has created the Network Assurance Engine, a software solution that brings formal verification techniques into networking.
By using data collection, comprehensive network modeling, and intelligent analysis, the Cisco Network Assurance Engine mathematically verifies and validates entire networks for correctness even as they are reconfigured. This accelerates troubleshooting and allows network managers to anticipate potential issues before they affect the business while maintaining high service levels with less effort.
The Cisco Application Visibility and Control (AVC) solution deploys a holistic approach for managing quality of service (QoS) technologies. It intelligently prioritizes traffic for critical applications while reducing or preventing traffic from noncritical or unwanted applications in an attempt to improve network and application performance over a wide area network (WAN).
Software-defined Wide Area Networks (SD-WAN) are virtualizations of on-premise infrastructure, cloud services, and any combination of transport services (MPLS, LTE and broadband) with the aim of intelligently coordinating traffic more securely and efficiently between SD-WAN resources and users